/* CIFSDD - dd for SMB. IO routines, generic and specific. Copyright (C) James Peach 2005-2006 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include "includes.h" #include "system/filesys.h" #include "libcli/raw/libcliraw.h" #include "libcli/libcli.h" #include "lib/cmdline/popt_common.h" #include "cifsdd.h" /* ------------------------------------------------------------------------- */ /* UNIX file descriptor IO. */ /* ------------------------------------------------------------------------- */ struct fd_handle { struct dd_iohandle h; int fd; }; #define IO_HANDLE_TO_FD(h) (((struct fd_handle *)(h))->fd) static bool fd_seek_func(void * handle, uint64_t offset) { ssize_t ret; ret = lseek(IO_HANDLE_TO_FD(handle), offset, SEEK_SET); if (ret < 0) { fprintf(stderr, "%s: seek failed: %s\n", PROGNAME, strerror(errno)); return(false); } return(true); } static bool fd_read_func(void * handle, uint8_t * buf, uint64_t wanted, uint64_t * actual) { ssize_t ret; ret = read(IO_HANDLE_TO_FD(handle), buf, wanted); if (ret < 0) { fprintf(stderr, "%s: %llu byte read failed: %s\n", PROGNAME, (unsigned long long)wanted, strerror(errno)); return(false); } *actual = (uint64_t)ret; return(true); } static bool fd_write_func(void * handle, uint8_t * buf, uint64_t wanted, uint64_t * actual) { ssize_t ret; ret = write(IO_HANDLE_TO_FD(handle), buf, wanted); if (ret < 0) { fprintf(stderr, "%s: %llu byte write failed: %s\n", PROGNAME, (unsigned long long)wanted, strerror(errno)); return(false); } *actual = (uint64_t)ret; return(true); } static struct dd_iohandle * open_fd_handle(const char * path, uint64_t io_size, int options) { struct fd_handle * fdh; int oflags = 0; DEBUG(4, ("opening fd stream for %s\n", path)); if ((fdh = talloc_zero(NULL, struct fd_handle)) == NULL) { return(NULL); } fdh->h.io_read = fd_read_func; fdh->h.io_write = fd_write_func; fdh->h.io_seek = fd_seek_func; if (options & DD_DIRECT_IO) { #ifdef HAVE_OPEN_O_DIRECT oflags |= O_DIRECT; #else DEBUG(1, ("no support for direct IO on this platform\n")); #endif } if (options & DD_SYNC_IO) oflags |= O_SYNC; oflags |= (options & DD_WRITE) ? (O_WRONLY | O_CREAT) : (O_RDONLY); fdh->fd = open(path, oflags, 0644); if (fdh->fd < 0) { fprintf(stderr, "%s: %s: %s\n", PROGNAME, path, strerror(errno)); talloc_free(fdh); return(NULL); } if (options & DD_OPLOCK) { DEBUG(2, ("FIXME: take local oplock on %s\n", path)); } SMB_ASSERT((void *)fdh == (void *)&fdh->h); return(&fdh->h); } /* ------------------------------------------------------------------------- */ /* CIFS client IO. */ /* ------------------------------------------------------------------------- */ struct cifs_handle { struct dd_iohandle h; struct smbcli_state * cli; int fnum; uint64_t offset; }; #define IO_HANDLE_TO_SMB(h) ((struct cifs_handle *)(h)) static bool smb_seek_func(void * handle, uint64_t offset) { IO_HANDLE_TO_SMB(handle)->offset = offset; return(true); } static bool smb_read_func(void * handle, uint8_t * buf, uint64_t wanted, uint64_t * actual) { NTSTATUS ret; union smb_read r; struct cifs_handle * smbh; ZERO_STRUCT(r); smbh = IO_HANDLE_TO_SMB(handle); r.generic.level = RAW_READ_READX; r.readx.in.file.fnum = smbh->fnum; r.readx.in.offset = smbh->offset; r.readx.in.mincnt = wanted; r.readx.in.maxcnt = wanted; r.readx.out.data = buf; /* FIXME: Should I really set readx.in.remaining? That just seems * redundant. */ ret = smb_raw_read(smbh->cli->tree, &r); if (!NT_STATUS_IS_OK(ret)) { fprintf(stderr, "%s: %llu byte read failed: %s\n", PROGNAME, (unsigned long long)wanted, nt_errstr(ret)); return(false); } /* Trap integer wrap. */ SMB_ASSERT((smbh->offset + r.readx.out.nread) >= smbh->offset); *actual = r.readx.out.nread; smbh->offset += r.readx.out.nread; return(true); } static bool smb_write_func(void * handle, uint8_t * buf, uint64_t wanted, uint64_t * actual) { NTSTATUS ret; union smb_write w; struct cifs_handle * smbh; ZERO_STRUCT(w); smbh = IO_HANDLE_TO_SMB(handle); w.generic.level = RAW_WRITE_WRITEX; w.writex.in.file.fnum = smbh->fnum; w.writex.in.offset = smbh->offset; w.writex.in.count = wanted; w.writex.in.data = buf; ret = smb_raw_write(smbh->cli->tree, &w); if (!NT_STATUS_IS_OK(ret)) { fprintf(stderr, "%s: %llu byte write failed: %s\n", PROGNAME, (unsigned long long)wanted, nt_errstr(ret)); return(false); } *actual = w.writex.out.nwritten; smbh->offset += w.writex.out.nwritten; return(true); } static struct smbcli_state * init_smb_session(struct resolve_context *resolve_ctx, struct event_context *ev, const char * host, const char **ports, const char * share, struct smbcli_options *options) { NTSTATUS ret; struct smbcli_state * cli = NULL; /* When we support SMB URLs, we can get different user credentials for * each connection, but for now, we just use the same one for both. */ ret = smbcli_full_connection(NULL, &cli, host, ports, share, NULL /* devtype */, cmdline_credentials, resolve_ctx, ev, options); if (!NT_STATUS_IS_OK(ret)) { fprintf(stderr, "%s: connecting to //%s/%s: %s\n", PROGNAME, host, share, nt_errstr(ret)); return(NULL); } return(cli); } static int open_smb_file(struct smbcli_state * cli, const char * path, int options) { NTSTATUS ret; union smb_open o; ZERO_STRUCT(o); o.ntcreatex.level = RAW_OPEN_NTCREATEX; o.ntcreatex.in.fname = path; /* TODO: It's not clear whether to use these flags or to use the * similarly named NTCREATEX flags in the create_options field. */ if (options & DD_DIRECT_IO) o.ntcreatex.in.flags |= FILE_FLAG_NO_BUFFERING; if (options & DD_SYNC_IO) o.ntcreatex.in.flags |= FILE_FLAG_WRITE_THROUGH; o.ntcreatex.in.access_mask |= (options & DD_WRITE) ? SEC_FILE_WRITE_DATA : SEC_FILE_READ_DATA; /* Try to create the file only if we will be writing to it. */ o.ntcreatex.in.open_disposition = (options & DD_WRITE) ? NTCREATEX_DISP_OPEN_IF : NTCREATEX_DISP_OPEN; o.ntcreatex.in.share_access = NTCREATEX_SHARE_ACCESS_READ | NTCREATEX_SHARE_ACCESS_WRITE; if (options & DD_OPLOCK) { o.ntcreatex.in.flags |= NTCREATEX_FLAGS_REQUEST_OPLOCK; } ret = smb_raw_open(cli->tree, NULL, &o); if (!NT_STATUS_IS_OK(ret)) { fprintf(stderr, "%s: opening %s: %s\n", PROGNAME, path, nt_errstr(ret)); return(-1); } return(o.ntcreatex.out.file.fnum); } static struct dd_iohandle * open_cifs_handle(struct resolve_context *resolve_ctx, struct event_context *ev, const char * host, const char **ports, const char * share, const char * path, uint64_t io_size, int options, struct smbcli_options *smb_options) { struct cifs_handle * smbh; if (path == NULL || *path == '\0') { fprintf(stderr, "%s: missing path name within share //%s/%s\n", PROGNAME, host, share); } DEBUG(4, ("opening SMB stream to //%s/%s for %s\n", host, share, path)); if ((smbh = talloc_zero(NULL, struct cifs_handle)) == NULL) { return(NULL); } smbh->h.io_read = smb_read_func; smbh->h.io_write = smb_write_func; smbh->h.io_seek = smb_seek_func; if ((smbh->cli = init_smb_session(resolve_ctx, ev, host, ports, share, smb_options)) == NULL) { return(NULL); } DEBUG(4, ("connected to //%s/%s with xmit size of %u bytes\n", host, share, smbh->cli->transport->negotiate.max_xmit)); smbh->fnum = open_smb_file(smbh->cli, path, options); return(&smbh->h); } /* ------------------------------------------------------------------------- */ /* Abstract IO interface. */ /* ------------------------------------------------------------------------- */ struct dd_iohandle * dd_open_path(struct resolve_context *resolve_ctx, struct event_context *ev, const char * path, const char **ports, uint64_t io_size, int options, struct smbcli_options *smb_options) { if (file_exist(path)) { return(open_fd_handle(path, io_size, options)); } else { char * host; char * share; if (smbcli_parse_unc(path, NULL, &host, &share)) { const char * remain; remain = strstr(path, share) + strlen(share); /* Skip over leading directory separators. */ while (*remain == '/' || *remain == '\\') { remain++; } return(open_cifs_handle(resolve_ctx, ev, host, ports, share, remain, io_size, options, smb_options)); } return(open_fd_handle(path, io_size, options)); } } /* Fill the buffer till it has at least need_size bytes. Use read operations of * block_size bytes. Return the number of bytes read and fill buf_size with * the new buffer size. * * NOTE: The IO buffer is guaranteed to be big enough to fit * need_size + block_size bytes into it. */ bool dd_fill_block(struct dd_iohandle * h, uint8_t * buf, uint64_t * buf_size, uint64_t need_size, uint64_t block_size) { uint64_t read_size; SMB_ASSERT(block_size > 0); SMB_ASSERT(need_size > 0); while (*buf_size < need_size) { if (!h->io_read(h, buf + (*buf_size), block_size, &read_size)) { return(false); } if (read_size == 0) { h->io_flags |= DD_END_OF_FILE; break; } DEBUG(6, ("added %llu bytes to IO buffer (need %llu bytes)\n", (unsigned long long)read_size, (unsigned long long)need_size)); *buf_size += read_size; dd_stats.in.bytes += read_size; if (read_size == block_size) { dd_stats.in.fblocks++; } else { DEBUG(3, ("partial read of %llu bytes (expected %llu)\n", (unsigned long long)read_size, (unsigned long long)block_size)); dd_stats.in.pblocks++; } } return(true); } /* Flush a buffer that contains buf_size bytes. Use writes of block_size to do it, * and shift any remaining bytes back to the head of the buffer when there are * no more block_size sized IOs left. */ bool dd_flush_block(struct dd_iohandle * h, uint8_t * buf, uint64_t * buf_size, uint64_t block_size) { uint64_t write_size; uint64_t total_size = 0; SMB_ASSERT(block_size > 0); /* We have explicitly been asked to write a partial block. */ if ((*buf_size) < block_size) { if (!h->io_write(h, buf, *buf_size, &write_size)) { return(false); } if (write_size == 0) { fprintf(stderr, "%s: unexpectedly wrote 0 bytes\n", PROGNAME); return(false); } total_size += write_size; dd_stats.out.bytes += write_size; dd_stats.out.pblocks++; } /* Write as many full blocks as there are in the buffer. */ while (((*buf_size) - total_size) >= block_size) { if (!h->io_write(h, buf + total_size, block_size, &write_size)) { return(false); } if (write_size == 0) { fprintf(stderr, "%s: unexpectedly wrote 0 bytes\n", PROGNAME); return(false); } if (write_size == block_size) { dd_stats.out.fblocks++; } else { dd_stats.out.pblocks++; } total_size += write_size; dd_stats.out.bytes += write_size; DEBUG(6, ("flushed %llu bytes from IO buffer of %llu bytes (%llu remain)\n", (unsigned long long)block_size, (unsigned long long)block_size, (unsigned long long)(block_size - total_size))); } SMB_ASSERT(total_size > 0); /* We have flushed as much of the IO buffer as we can while * still doing block_size'd operations. Shift any remaining data * to the front of the IO buffer. */ if ((*buf_size) > total_size) { uint64_t remain = (*buf_size) - total_size; DEBUG(3, ("shifting %llu remainder bytes to IO buffer head\n", (unsigned long long)remain)); memmove(buf, buf + total_size, remain); (*buf_size) = remain; } else if ((*buf_size) == total_size) { (*buf_size) = 0; } else { /* Else buffer contains buf_size bytes that we will append * to next time round. */ DEBUG(3, ("%llu unflushed bytes left in IO buffer\n", (unsigned long long)(*buf_size))); } return(true); } /* vim: set sw=8 sts=8 ts=8 tw=79 : */